Question: Simplify the following expression: $\sqrt{80}+\sqrt{5}-\sqrt{20}$
Solution: First, try to factor any perfect squares out of the radicals. $= \sqrt{80}+\sqrt{5}-\sqrt{20}$ $= \sqrt{16 \cdot 5}+\sqrt{5}-\sqrt{4 \cdot 5}$ Separate the radicals and simplify. $= \sqrt{16} \cdot \sqrt{5}+\sqrt{5}-\sqrt{4} \cdot \sqrt{5}$ $= 4\sqrt{5}+\sqrt{5}-2\sqrt{5}$ Finally, simplify by combining the terms. $= ( 4 + 1 - 2 )\sqrt{5} = 3\sqrt{5}$